Film feeding apparatus



Jan. 21, 1941. Q. J. HOLMES I 2,229,455

FILM FEEDING APPARATUS Filed Jan. 29, 1940 4 Sheets-Sheet l INVENTOR.

ATTORNE'YQ Jan. 21, 1941. o. .J. HOLMES FILM FEEDING APPARATUS Filed 'Jan. 29, 1940 4 Sheets-Sheet 2 IN VENTOR. lfo'fizas ATTORNEY? Oa'auwf Jan. 21, 1941.

o. J. HOLMES FILM FEEDING APPARATUS Filed Jan. 29, 1940 4 Sheets-Sheet 3 INVENTOR. HaJmas ATTORNEY:

BY. aicar J:

' Jan. 21,1941.

0. J. HOLMES FILM FEEDING APPARATUS INVENTOR. Qatar Jflahrzej ATTORNEYfi.

4 Sheets-Sheet 4 Filed Jan. 29, 19 40 Patented Jan. 21, 1941 UNITED STATES PATENT OFFICE 2,229,455. l FILM FEEDING APPARATUS Oscar J. Holmes, Chicago, Ill. Application January 29, 1940, Serial No. 316,086

17 Claims.

This invention relates to sound-on-film reproducing or recording apparatus and more particularly to a control mechanism for maintaining a film at constant velocity for sound translation.

The apparatus for recording and reproducing systems now commonly includes means such as a flywheel by which it is sought to smooth out the irregularities of motion of the film past the recording or reproducing point. The undampened flywheel of relatively large mass as at first employed possessed a number of disadvantages, chief among which were that it formed an oscillating system with the film-directing idle rollers 5 or driving sprockets, which system had a period of its own and, instead of absorbing all irregularities in the film motion, aggravated many such irregularities. It was subsequently proposed to dampen the flywheel in various ways, employing a viscous incompressible fluid such as oil which exerted a drag upon the flywheel which it was thought would tend to resist a change in velocity of the flywheel. However, such constructions have not been entirely satisfactory for a number of reasons, of which the following appear to applicant to be the most important.

The viscosity of the incompressible fluid or Oil varies with temperature to a great degree. When the machine is cold, the oil is of such relatively high viscosity that it imposes a great drag upon the flywheel, places a great strain upon the fllm and film-driving wheels, and is, generally speaking, quite unsatisfactory for the performance of its intended function. As the machine warms up -or becomes hot, the viscosity of the oil changes considerably so that its drag upon the flywheel varies during the heating-up period and, instead of ironing out irregularities in the film motion, it causes and accentuates such irregularities. 40 When the oil used has the best or most advantageous Viscosity for operation after the machine has reached the normal operating temperature, its viscosity, when the machine first startsup and during the initial portion of the heating-up period, is so great that it may be said to be en tirely unsatisfactory. Sacrifice, therefore, has to be made in regard to the viscosity of the oil for best operating conditions when the oil has become fully heated in order that some satisfaction of operation may be obtained when starting the machine and during the heatingmp period.

Furthermore, in such oil-dampened flywheel systems and because of the incompressible character of the fluid or oil, the length of the film 5, loops between the drum or sprocketon the fly- (c1. zip-2.3)

wheel shaft and the rollers or sprockets over which the film passes to and from the drum or sprocket on the flywheel shaft becomes greater or less as irregularities in the motion of the sfilm cause the film to speed up or slow down and as spliced joints in the film pass over thedrum or sprocket on the flywheel shaft. Also, it hastbeen observed that the particles at the edges or the sprocket openings'on one side of the film, that project outwardlythe minutest amount from the face of the film, cause,as the film passes over the drum or sprocket on the flywheel shaft, this oscillating increase and decrease in the'size of these film loops. -As the film' loop in advance of the flywheel driving and driven drum or sprock'et tends to increase in size due to aniincrease inthe longitudinal speed of the film; the film itself stores up a certain amount of energy which tends to cause the filmto slide or slip relatively to the drum or sprocket. and toincre'ase without changing the speed of' the drum the length of the loop on the other side ofthe drum, which causes distortion of the sound, and, if this slippage is resisted, sets up a transverse vibration or ripple motion which is transmitted by the film. from the loop tothe film on the; drum or sprocket. When the film loop between the flywheel driving and driven drum and the'fol- "lowing idle roller or sprocket tends toincrease due to a change in the longitudinalvelocity'of the'film, the body of the film in this loop tends to cause the film to slip re'arwardly relativ to the flywheel driving and'driven drum orsprocket without changing the speed thereof and to increase the length of the loop in advance of such drum or sprocket which, of course, produces distortion and, if this slippage is resisted, sets up a transverse vibration or ripple motion which, as before stated, is'rreflected upon the portion of the film on the flywheel driving and driven drum or sprocket.

This flapping of. the film over the idlerollers or sprockets on opposite sides of the drum or sprocket on the flywheel shaft is thus reflected in a flapping of the film on the flywheel driving and driven drum or sprocket and, since the sound is reproduced from the film as" it passes over suchdrum or sprocket, this flapping of the film and/or the slippage of the film relative tothe fiywheel driving and driven drum or sprocket causes distortion of the sound and creates a masking. oscillation ofaudible frequency and objectionable intensity such as to seriously impair the fidelity of the'sound'repr'oduced. In the case of the recorder, this flapping of the film and/or the produces distortions which are worse in many cases than those sought to be avoided by the substitution of such a flywheel for a previouslyem ployed undampened flywheel. a l

It is, therefore, an object of applicants inven-' tion to provide means tending sufficie'ritly' toire sist change in longitudinal velocity of ,the film to eliminate detectable distortions of sound "pro duced by changes in such longitudinalvelocity andyat the same time, tending to resist or prevent' the generation of aQlongitudinallyreflected ripplerim'otion or .wave and/or fiapping'of the film and consequent audible distortions. which are producedathereby.

A' further. object of the invention is to provide a novel inertia-control device utilizing a compressible fluid fo'r'maintainingthe motion of the film uniform and unaffected by changes inthe temperature of thefluid; unaffected by spliced joints .in'thefilm; and unafiected .by other forces or conditions which tendto cause a change in the velocity ofi'the film. i

Other and further objects and advantages of the invention will be apparent from the following description when taken .in' connection with the accompanying. drawings. a

Figure? lrshows an illustrative embodiment'of the invention asemployed in a sound-reproducing apparatus," this view being afragmentaryview. in elevationv of such an'apparatusi Figure 2is a fragmentary vertical section taken substantially along the line 2-4 of Figure 3.

Figure" 3. "Jis a fragmentary vertical section taken.-along'ithe line 3-4 of Figure 2.

Figure4is afragmenta'ry horizontal section takemalong the line 44' of Figure 2. Figure-.5 is :a fragmentary view in elevation of a modified-form of the invention.

Figure 6: is a fragmentary view in section taken along Ithe' line I6+-6= of Figure l 5.

Figure T is afrzigmentary vertical section taken alongith'e line 1.-'l of Figure 6. l I l Figure 8. is a view in perspective of an element of the .device shown in Figures'5 to '7, inclusive.

Figure 9.is a fragmentary view in elevation of another. modified form of the invention; and

- Figure .l'flcis alfragmentary vertical section taken alongtthe line'llllll of'Figure9. 1

As shown in Figures 1 to 3 for purposes of illus tration, the invention may be". embodied in a sound-on-film 'motion picture reproducer '2 hav-:

ing ianielectrici-motor 4"as a common'power source for drivingithemechanism of the sound-picture machine!) This mechanism includes an intermittent motion 6 of any suitable or conventional design for intermittently feeding film into-and out of the picture projecting beam; a feed"s'procket or roller-8"o'ver which the film passes from the intermittent motion 6; aspring-tensioned arm I0 carrying th'e'usual film-engaging roller or rollers forrriaintaining the film upon the sprocket 8; a drurn-lt' about which the'filmpasses from the s'procket t 'and fromwhich drum thefll passes over another feed sprocket or roller M with which cooperates a spring-tensioned guide 16 and a third feed sprocket or roller I3 with which a spring-tensioned guide 20 cooperates, the film passing from the sprocket 18 between pairs of opposed guide rollers 22 to the film takeup roll or reel 24. The film extends beyond the outer edge of the drum i2 so that the sound track thereon lies outside this edge of the drum and, passes agrossabeam of light projected upon the film by an optical system 26 ;of suitable conventional design from a light source 28, the beam The 'motor i is connected by the coupling 32 (Fig. 2)-to the shaft '34 provided with a worm gear 35,.the shaft 34 being mounted in suitable anti-friction bearings 38 supported in opposed walls orpartitions of amechanism housing 40 secured to: or. cast integrally with the side wall of the housing, or one portion 42 of the housing, for the: sound head of the machine. The worm 3B drives inter-meshing gears 44 and 46, the gear ttbeingsecuredto and driving the shaft 48 of; the ,feed sprocket or roller l4, and thegear ifi-beingsecured to and driving the shaft 50 of the feed-sprocket or. roller 18. The shaft 50 may also drive through the pulley 52 and belt 54 the take-uprolhor r eel 24. The shaft 18 also drives through an; appropriate mechanism, of which gear 56;secured;to the shaft 48 forms a part, the feedsprocket or roller 8 and the intermittent motion; 6-. jfI-he drum i2 is carried upon the shaft 58v which is preferably carried in ball bearings 60; and 62, mounted in a wall of the portion 42 of the housingiorthe sound headand a boss or bracket formed :upon or, secured to the mecha nism housing 40: An inertia member or flywheel this. pinned or keyed to the outer end of the shaft :58; The inertia member or flywheel 64, as shown-in Figs. 1 to 3, comprises a casting havinga-,centra1 apertured disk-like portion or hub 66 and radially-directed, outwardly-extending, angularlyespaced .blades 68, or fins of appreciable ,length."The flywheel is housed within a voluteyfluid,confining'housing or casing 10 secured orattachedin any-convenient manner to the housing for the sound head-or to the portion Z-thereofi. ,,T he flywheel-circumscribing wall of the housing orcasinglfl may comprise a portion 12.) ofv circular; configuration in cross-section merging intoaportion l4 ofspiral configuration in--cros s-section, the-portion of circular configuration. being connected to the portion of spiral configuration by a shelf-like portion I6 against whichthecompressible fluid, preferably air, within thehousing is compressed or driven. An openinglin the rearwall-IB of the housing or casing lo which may-beprovided by an enlargement of the aperture-Bil through which the shaft 58 passes, provides fluid orair admission means or portion the housing or casing 10. A fluid or air exhaustinggmeans or port ,may be provided by an opening-82 in .theshelf-like portion 16 of the flywheel housing or casing and the rate of flow ofthe compressible fluid or air through this openingmay be regulated by a valve 84 comprising aplate pivoted to. the under surface 'of the'shelf-like portion 16 and provided with an operating knob orpin 86, by which the valve may 'be swung to regulate the size of the opening through which the compressible fluid or air may beexhausted from the flywheel housing or casing.

In the operation of the machine, the film passing about a portion of the drum I2 drives this drum, the shaft 58, and the inertia member or flywheel 64. The flywheel, by virtue of its construction in which, as compared with prior flywheels, a considerable amount of material is removed to form the blades or fins 6B, is considerably lighter in weight than such prior flywheels. Hence, this novel flywheel reducesthe wear upon the film caused by its engagement with the roller I2 frictionally driven by the film. The compression of the confined fluid or air by the blades as they sweep past the shelf I6 in a clockwise direction, the displacing of the fluid or air as the tips of the blades rotate in proximity to the wall portion I2 of circular configuration, and the expansion of the fluid or air above the shelf I6 within the limits of the portion I4 of spiral configuration produce a retarding or dampening effect upon the flywheel and increase the inherent tendency of the fluid, in acting upon the relatively large facial areas of the blades, to oppose a change in speed of the flywheel. These retarding forces are sufiicient to dampen the flywheel against changes in speed due to changes in the longitudinalvelocity of the film occurring sufiiciently rapidly to produce, if undampened, an audible sound distortion but, at the same time, prevent any. detectable formation of a wave or ripple motion in the film which would be reflected to the portion of the film on the drum I2 and cause an audible sound distortion.

It appears, from exhaustive tests and observations of machines provided with this flywheel dampened by a compressible fluid, that the longitudinal velocity of the film is maintained sufficiently constant against suddenly occurring changes as to prevent any audible distortion of sound and at the same time eliminates the flapping of the film heretofore caused by the oscillating increase and decrease in the length of the portion of the film or loop between the drum I2 and the feed sprocket or roller I4 and/or the sprocket or roller 8. Also, the compressible fluid exerts a retarding effect which does not vary with the temperature of the fluid.

It will, of course, be apparent that compressible fluids other than air may be employed if desired, although air is preferably employed since. it entails no supply cost, does not cause a breakdown of the apparatus if the fluid medium leaks out of its confining casing, and reduces the cost of the confining casing which it is obvious does not need to be rendered proof against leakage of the medium. Where a compressible fluid other than air is employed, the fluid admission and exhaust ports may be eliminated or such ports may be connected by an external or internal conduit or duct.

In the form of the invention shown in Figures 5 to 8, the housing or casing 08 for the flywheel 64 is preferably of cylindrical form and comprises a foraminous cage or wire guard seated of a disk 94 secured to the housing for the sound head or to any other suitable fixed portion of the machine. The cage 90 is fastened to the disk 94 as by a plurality of angul'arly-spaced screws 96, carried by the ring or rim 98 of the cage or guard and threaded intothe disk 94. Spacing sleeves I00 may be used in connection with the screws 96 to maintain the face portion of the cage or guard in proper aced relation to the disk 94. The blades or fin ,68 of the flywheel 64 are in this form of the invention provided at their tips with strips or p-ieces I02 of felt or similar cushioning material, secured to the blades as by of relatively thin sheet metal or other suitable yielding material, having opposed wing portions I08 and III) connected by a flange portion II2 fitting into the space between a pair of blades at the hub thereof and receiving a fastener H4 for securing the yieldable blade I06 to the hub portion 66 of the flywheel. When thus secured, the wing-like portion I08, which is shorter than the wing-like portion H0 of the blade I06, yieldably engages a face of one of the pair of blades or fins 68 of the flywheel, while the wing-like portion H0 of the blade yieldably engages the felt strip I02carried by the other blade 68 of the pair of adjacent blades of the flywheel. The wing-like portions I I0 of all the blades I06 extend well beyond the edges of the flywheel blades 68 but terminate a substantial distance inwardly of the cage or guard 90. During operation, the flywheel of this form of the invention rot-ates in a. clockwise direction as seen in Figure 5. The air, which is driven or displaced by the flywheel as it rotates, exerts a retarding effect upon it sufficiently to maintain the film velocity substantially uniform as against forces tending to effect a sudden change in such velocity and at the same time this dampening effect does not cause flapping of the film. The yieldable or auxiliary blade I06 provide a very convenient means of increasing the facial areas of the flywheel blades without appreciably increasing the weight of the flywheel and, being yieldable, prevent the currents of compressible fluid from causing chattering of the flywheel. Also, it has been found that these yieldable blades, in yielding relative to the blades or fins 68 of the flywheel, tend to act as impelling or retarding wings, further resisting any sudden change in the velocity of the flywheel and preventing the flywheel from becoming part of an oscillating system with the film-driving rollers or sprockets. The housing 88 functions as a guard and is preferably formed of wire as shown, so as not to effect to any appreciable extent the free flow of the compressible fluid or air under the driving force of the flywheel. The felt pieces I02 cushion the blades I06 so that no vibrations will be set up between these blades and the blades 68 of the flywheel proper. In the form of the invention shown in Figures 5 to 8, the flywheel 64, with the auxiliary blades I06, is pinned or keyed to the shaft 58 to rotate therewith at all times.

In the form of the invention shown in Figures 9 and 10, the flywheel 64, provided with the auxiliary blades I06 between alternate pairs of flywheel blades 68, is mounted on an outer end portion IIB of the shaft 58 by roller bearings H8 and I20, having a close fit between the hub 66 f of the flywheel and the shaft portion II6 so within the outwardly bent peripheral flange 92 that the flywheel 64 is frictionally driven by the shaft. -A solid flywheel I22 is pinned or keyed to the shaft 58 as by set screw I24 in, axially spaced relation to the fllywheel 64 and a spacing sleeve I26 is interposed between the flywheel and the rear roller bearing I20, the sleeve having frictional engagement with the flywheel and the bearing, if desired, so .as to apply an additional friction tending to cause rotation of the flywheel 64 with flywheel I22 and the shaft 58. Axial movement of the flywheel 64 is prevented by the sleeve I26 and a washer I28 overlapping the bearby-a screw I30. 'The flywheel 122 may, of course, be lighter in weight than the solid flywheels heretofore employed, and it is dampened by the frictionally driven and frictionally reactive flywheel 64,.which performs its dampening effect in the same manner as the flywheel 64 with the auxiliary blades I06 as previously described with this inherent deficiency of a system employing a solid undampened flywheel.

It will, therefore, be seen that applicant has provided means tending sufflclently to resist change in longitudinal velocity of the film to eliminate detectable distortions of sound produced by changes in such longitudinal velocity and, at the same time, tending to resist or prevent the generation of a longitudinally reflected ripple motion or wave and/or flapping of the film and consequent audible distortions which are produced thereby; and a novel inertia-control deviceutilizing a compressible fluid for maintaining the motion of the film uniform and unaffected by changes in the temperature of the fluid; unaffected by spliced joints in the film; and unafiected by other forces or conditions which tend to cause a change in the velocity of the film.

I claim:

. 1. A phonographic apparatus comprising a frictionally driven record carrier, an inertia member coupled to said carrier and compressible fluid 'means dampening the inertia member against variations in speed.

2. A phonographic apparatus comprising a frictionally driven record carrier, a flywheel coupled to said carrier and compressible fluid. means for dampening the flywheel against variations in speed.

3. Film feeding apparatus comprising a film carrier frictionally driven by the film, an inertia member coupled to said carrier and operatively associated with means providing radial fins operating in an atmosphere of compressible fluid reacting thereupon to dampen the inertia member against changes in velocity.

- 4. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a rotary inertia member coupled to the carrier, and means rotating with the inertia member in an atmosphere of compressible fluid for dampening the inertia member against changes in velocity as spliced joints of the film pass the carrier.

5. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a flywheel coupled to said carrier, a housing for said flywheel filled with a compressible fluid, and means rotating with the flywheel in the atmosphere of compressible fluid in the housing for dampening the flywheel against changes in velocity.

6. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a flywheel coupled to said carrier, a housing for said flywheel filled with a compressible fluid, and means rotating with the flywheel for propelling the compressible fluid in the housing whereby the reaction of the compressible fluid dampens the flywheel against changes in velocity.

7. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a flywheel coupled to the carrier, a container providing a ing 1 l8 and secured to the end of the shaft 58 aschamber housing the flywheelandair admission and exhau-st penings into saidfchamben-saidflywheelhaving radially extended fins for circulating the air in said chamber from the air admission openings through the air exhaust opening whereby the reaction of the air upon.

the fins .of the flywheel dampens the flywheel against variations. in velocity.

8. In a film feeding apparatus, a rotary fihn carrier frictionally driven by the film, a flywheel coupled to the carrier, a container providing a chamber housing the flywheel, air admission and exhaust openings into said chamber, said flywheel having radially extended fins for circulating the air in said chamber from the air admission openings through the air exhaust opening whereby the reaction of the air upon the fins of the flywheelv dampens the flywheel against variation in velocity, and means for adjustably regulating the amount of air flowing through one. of said chamber openings whereby to adjustably regulate, the dampening effect of the air upon the flywheel.

9. In a filmfeeding apparatus, a rotary filmcarrier frictionally driven by the film, a flywheel coupled to the carrier, a container providing a volute chamber housing the flywheel and air admission and exhaust openings into said chamber, said flywheel having radially extended fins for circulating the air in said chamber from the air admission openings through the air exhaust opening whereby the reaction of the air upon the fins of the flywheel dampens the flywheel against variations in velocity.

10. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a flywheel coupled to said carrier and means including a flexible blade rotating with-the flywheel in an atmosphere of compressible fluid for dampening the flywheel against variations in velocity.

11. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a flywheelcoupled to said carrier, and means including a plurality of flexible and inflexible blades rotating with the flywheel in an atmosphere of compressible fluid for dampening the flywheel against variations in velocity.

12. In a film feeding apparatus, a rotary film carrier frictionally .driven by the film, a flywheel coupled to said carrier, said flywheel having a plurality of. radially extending inflexible fins, a housing for saidflywheel filled with a compressible fluid, and a plurality of flexible blades mounted on said flywheel in yielding relation to said fins and coupling with said fins to dampen the flywheel against variations in velocity.

13. In a film feeding apparatus, a rotary film carrier frictionally driven by the film, a solid flywheel coupled to said carrier, and means frictionally coupled to said solid flywheel and includin means rotating in an'atmosphere of compressible fluid for'frictionally applying dampening forces to the solid flywheel.

14. In a fllm'feeding apparatus, a rotary jfilm carrier frictionally driven by the film, a solid flywheel coupled to said carrier and means frictionally coupled'to thefiywheeland the carrier and rotating in an atmosphere of compressible fluid for frictionally dampening the solid flywheel and the carrier against variations in velocity.

15. -In a film feeding apparatus, a rotary film.

carrier frictionally driven by the film, a solid flywheel'coupledto the carrier, a second flywheel.

coupled to the solid flywheel and having radial flns rotating-in an atmosphere of compressible fluid for dampening the solid flywheel against variations in velocity.

16. In a film feeding apparatus, a rotary film carrier driven by the film, a solid flywheel coupled to said carrier, a second flywheel coupled to the solid flywheel, a housing for said flywheel filled with a compressible fluid, said second flywheel having radially projecting fins propelling the compressible fluid whereby the reaction of the compressible fluid on the second flywheel serves through the second flywheel to dampen the solid flywheel against variations in velocity.

1'7. In a film feeding apparatus, a rotary film carrier driven by the film, a solid flywheel coupled to said carrier, a second flywheel coupled to the solid flywheel, a housing for said flywheel filled with a compressible fluid, said second flywheel having radially projecting fins propelling the compressible fluid whereby the reaction of the compressible fluid on the second flywheel serves through the second flywheel to dampen the solid flywheel against variations in velocity, said fins of the second flywheel being inflexible, and a plurality of flexible blades mounted on said second flywheel in yielding relation to said flexible fins.

OSCAR J. HOLMES. 

